| 摘要 |
501,611. Artificial filaments, films, etc.; resinous condensation products; dyeing processes. SOC. INDUSTRIELLE DE MOY, and BURET, R. Sept. 11, 1937, No. 24828. [Classes 2 (ii), 2 (iii), and 15 (ii)] Regenerated cellulose threads, fibres, ribbons, and films possessing a high affinity for wool and silk dyestuffs, are obtained by incorporating in the cellulosic solution from which the materials are formed, a synthetic resin obtained by condensing an aldehyde with a phenol containing a substituent group in para position to the hydroxyl or a mixed synthetic resin obtained by reaction of a phenol or a phenol substitution derivative on a resin of the ureaaldehyde type; or by reaction of urea on a resin of the phenol-aldehyde type. Thio-urea may be used instead of urea. The resins employed are resistant to oxidation and have little or no tendency to discolour the threads containing them. These resins give a green colouration when treated with concentrated sodium hypochlorite solution whereas resins which readily darken by oxidation give a red colouration. In an example, a syrup is obtained by heating a mixture of p-cresol, formalin, and caustic soda solution, distilling volatile constituents, and adding more caustic soda. The syrup is further diluted with caustic soda solution and added to viscose at any stage of preparation of the latter. The viscose is spun into an acid-salt bath and the threads produced are subjected to finishing treatments. In another example, urea, formaldehyde solution, and caustic soda are heated together on a water-bath. After the reaction has slackened, phenol is added. Part of the mixture is distilled, more caustic soda is added to the syrup, and before use the syrup is mixed with dilute caustic soda solution. The diluted syrup is added to viscose which is spun into a bath containing sulphuric acid and sulphates. The threads are desulphured and bleached. In another example, formalin is mixed with thiourea, glycerine, and hydrochloric acid. The mixture is heated to boiling and then left to cool. While still hot, there is added to the solution a quantity of molten phenol. Caustic soda solution is added when the reaction has ceased. The diluted syrup is mixed with viscose which is then spun to form filaments. These are cut to staple fibres which may be mixed with wool. Thread or fabric containing the mixed fibres may be dyed in a single bath. Dyes may be added to the cellulosic solution before spinning. The solution may also contain additions of softeners such as glycerine, glycol, or camphor, or pigments, mordants, or oils. Specification 501,603 is referred to. |
